The present disclosure relates to composites, particularly, polymer coated composites comprising metal nanoparticles dispersed throughout the composite matrix, for use in selective laser sintering (SLS) application.
The medical community's reliance on three dimensional 3D printing for various applications is rapidly increasing and covers areas such as tissue and organ fabrication, customizable devices such as prosthetics, mouth guards, orthotics, hearing aids and implants, and pharmaceutical exploration related to controlled drug delivery and personalized drug production. Many of these medical applications require composite material that can inhibit bacterial, microbial, viral or fungal growth. Other products for 3D printing such as kitchen tools, toys, education materials and countless household items also provide a favorable environment for bacteria growth, and therefore antibacterial composite materials are also desirable for use in connection with these products. Due to the layered construction of 3D printed material, the potential for bacterial growth can be very significant, especially since certain bacterial strains can actually thrive within the detailed structural make-up of these materials. Washing alone does not completely sterilize the surfaces and crevasses of these products.
Therefore, there exists a need for new materials with antibacterial properties for 3D printing. One of the 3D printing methods is selective laser sintering (SLS), which is a common additive manufacturing (3D printing) technique. A detailed description of SLS technology can be found in U.S. Pat. Nos. 4,247,508, 4,863,538, 5,017,753, 5,597,589 and 6,110,411, each incorporated herein by reference. SLS printing typically employs powdered plastics/polymers as build materials for printing objects. Most SLS materials are composites of polyamide (nylon) with or without additives such as powdered glass, carbon fibers, aluminum powder, etc. The powder is sintered into shape by a laser in a layer-by-layer fashion to build the objects from “scratch”. Laser sintering usually uses particles ranging from about 50 to about 300 microns, where the degree of detail is limited only by the precision of the laser and fineness of the powder. The detail and intricacy of the objects derived through the SLS process is remarkable but also creates potential scaffolds for bacterial or microbial build-up, especially in applications related to health care and the food industry.